This proposal is for the Data Coordinating Center for the Soft Bifocal Contact Lens Myopia Control Study, a mulfl-center, randomized clinical trial designed to answer 3 important issues related to slowing eye growth in myopic children. We will determine whether soft bifocal contact lenses slow myopia progression in children. The soft bifocal contact lenses will create a wide distribution of peripheral defocus in myopic subjects, which will allow us to determine whether the amount of peripheral myopic defocus is related to slower myopia progression. Measuring the peripheral refractive error without contact lenses will allow us to monitor changes in eye shape to determine whether peripheral defocus primarily changes local eye growth or affects the growth of the entire eye. In this trial, 294 children aged 7 to 11 years with myopia will be randomly assigned to wear soft bifocal (either Biofinity Multifocal with +2.50 D add or with +1.50 add; Cooper Vision, Fairfield, NY) or single vision (Biofinity; Cooper Vision, Fairfield, NY) contact lenses. A comparison of the myopia progression experienced by the treatment groups will determine if the soft bifocal lenses slow myopia, while peripheral findings will provide additional information about the regulation of peripheral eye growth. As the Data Coordinating Center for the Soft Bifocal Contact Lens Myopia Control Study, we will complete the following Specific Aims: 1.) implement the protocol as designed by the Soft Bifocal Contact Lens Myopia Control Study Executive Committee; 2) implement data collection procedures via electronic data capture systems that ensure high-quality data in a secured fashion; and 3) analyze the data using appropriate statistical methodology and ensure that the results are accurately reported.